Study On The Impact Of Coincidence Windows To The System Performance And Image Quality Of Trans-PET

Positron emission tomography(PET) is a nuclear imaging technique that usesthe unique decay characteristics of radionuclides that decay by positron emission. Other than traditional medical imaging technique of reflecting anatomical information, PET can provide information about physiological metabolism and biochemical function of diseased region in molecular level. It is one of the most advanced non-invasive functional imaging technology at present.PET uses a characteristic technique—coincidence detection, which has improved the sensitivity dramatically. Optimal selection of the coincidence windows(include time window and energy window) may improve the image quality of PET. This article adopts Trans-PET? BioCaliburn LH system as a platform, and employs sensitivity, spatial resolution and image quality parameters to evaluate performance of the system and imagequality. To optimize the coincidence windows, control variables method is used to design experiments. The impact of different coincidence time window, energy window upper limit and lower limit to PET system and image quality is studied separately.Simulation experiment, phantom experiment and animal experiment are implemented to analyse the regularity. The appropriate range of the PET coincidence windows is preliminarily obtained according to the regularity from all the experimental research: the appropriate range of the PET time window is 3 ns, and the appropriate range of the PET energy window is(300~600)keV. It should be noted that PET coincidence windows are not invariable, the PET user still needs to make further optimization and adjustmentunder different experimental conditions(for instance, tracer dose, scanning time, and background)and purpose.Optimal selection of coincidence windows can help to improve the PET image quality almost with no increase of the cost, so study on the impact of coincidence windows to PET system performance and image quality is significant. Due to the differences on design, material, processing and software system between different PET systems, the result of research on impact of coincidence windows to PET system performance and image quality in this article is only applicable forTrans-PET? BioCaliburn LH system. As the study method is based on experimental analysis, the experimental phantoms and animals are adopted by general model, so it is completely portability. The study method described can be used as reference for other PET systems.